1) Field of the Invention
The present invention pertains to a wheelchair back support assembly that is designed to be retrofit to a wheelchair or to replace an existing back support of a wheelchair. The wheelchair back support assembly has a simple construction that is both lightweight and sturdy and includes a back support panel that can be contoured to match the back of the wheelchair user and springs that permit the back support to comfortably flex in response to movements of the back of the wheelchair user.
2) Description of the Related Art
Wheelchairs have various different constructions but many are constructed of tubular metal members that are connected together to form a rigid frame of the wheelchair. A wheelchair 10 of this type is shown in FIGS. 1 and 2. The metal construction of the wheelchair tubular members significantly contributes to the overall weight of the wheelchair. As seen in FIGS. 1 and 2, the tubular frame members include two side horizontal frame members 12 and one rear horizontal frame member 14 that are connected together to form a support for the seat of the wheelchair. Many of the connections between the tubular frame members of the wheelchair are telescoping connections where an end of one member is inserted into an end of another member. The connections are then secured by threaded fasteners, by spring biased detents, or by other equivalent means. The seat of the wheelchair shown is a soft xe2x80x9cslingxe2x80x9d type seat that is constructed of a piece of sturdy fabric 16 stretched across the side horizontal frame members 12 and in front of the rear horizontal frame member 14. The horizontal frame members 12, 14 are supported on the wheels of the wheelchair by a framework 18 of tubular members. The framework includes a pair of rear, lower vertical frame members 20 that are connected to the rear wheels 22 of the wheelchair. The pair of lower vertical frame members 20 are also connected with the side horizontal frame members 12 and the rear horizontal frame member 14 and terminate at their top ends (not shown) adjacent the horizontal frame members. An upper pair of vertical frame members 24 are connected to the top ends of the pair of vertical frame members 20.
The upper pair of vertical frame members 24 extend upwardly from the horizontal frame members 12, 14 to bent upper ends 26 of the vertical frame members that function as the handles of the wheelchair. This additional pair of vertical frame members 24 at the rear of the wheelchair are commonly referred to as the xe2x80x9ccanesxe2x80x9d of the wheelchair due to their shape. They support a soft xe2x80x9cslingxe2x80x9d type back 28 of the wheelchair that is commonly constructed of a piece of sturdy fabric. The pair of vertical canes 24 are often telescopically attached to the upper ends of the lower vertical frame members 20 attached to the wheelchair rear wheels. The canes 24 are secured to the lower vertical frame members 20 by threaded nut and bolt fasteners inserted through aligned holes of the frame members, by spring biased detents or by other equivalent means as discussed above.
In many prior art wheelchairs constructed of tubular frames similar to the wheelchair discussed above, there is no adjustability or only limited adjustability of the tubular frame members to accommodate wheelchair users of different physical characteristics, for example different sizes and different weights. In addition, wheelchairs with tubular frame members often have their back supports fixed rigidly to their seat supports, providing no adjustment of the back support to accommodate users of the wheelchair having different physical characteristics. Should a user of a wheelchair desire a specific configuration of a back support on the wheelchair to either accommodate their larger size or to more comfortably support their back, the wheelchair user was often required to purchase an entire new wheelchair that incorporated the specialized options such as a wider back support or a back support that tilts.
What is needed to overcome these disadvantages of existing wheelchairs is a back support assembly that is both lightweight and sturdy, is designed to be inexpensively retrofit to an existing wheelchair frame, is designed to comfortably support the back of wheelchair users of different sizes and having different physical characteristics, and also flexes and moves relative to the wheelchair in response to movements of the back, shoulders and arms of the wheelchair user to thereby provide comfortable dynamic support to the back of the wheelchair user.
The wheelchair back support assembly of the present invention overcomes the disadvantages associated with rigid, uncomfortable wheelchair back supports of wheelchair""s having tubular frame members by providing a back support assembly that can be inexpensively retrofit to an existing wheelchair frame replacing its original back support and which flexes and moves in response to movements of the wheelchair user.
The back support assembly of the invention includes a padded back panel constructed of composite materials or other similar types of materials that can be specifically molded or shaped in different sizes to conform to the back configurations of the wheelchair users of different sizes. The back panel is connected between a pair of side columns that have mounting poles at their bottom ends. The mounting poles are specifically designed to be telescopically received on tubular frame members of an existing wheelchair in place of the back support or canes of the wheelchair. The mounting poles are attached to the side columns of the back support assembly by inclination adjustment mechanisms that permit an adjustment of the angle of inclination of the back panel. In addition, the inclination adjustment mechanisms are connected to the side columns by a pair of spring assemblies that allow the back panel to flex comfortably relative to the mounting poles of the back support assembly. The pair of spring assemblies are mounted to the side columns by connectors that can be adjustably positioned along the lengths of the side columns, thereby adjusting the vertical position of the back panel relative to the wheelchair. In addition, the back panel is provided with a centered manual handle or, alternatively, a pair of manual handles may be attached to the side columns and adjustably positioned along the lengths of the side columns. The side columns are also designed to have additional components such as lateral torso supports and arm rests adjustably attached to the side columns.
The wheelchair back support assembly provides an inexpensive back support with a simple construction of only a few component parts that can be easily retrofit to a tubular frame of an existing wheelchair, replacing the wheelchair""s original back support. The back support assembly provides the wheelchair with a back support that can be provided in different sizes for the size and shape of the wheelchair user""s back, that can be adjustably positioned both angularly and vertically relative to the wheelchair, and that flexes as the wheelchair user moves on the wheelchair to comfortably support the wheelchair user.